John is leading a landscaping project with a water feature and needs to explain activity dependencies to his client. After connecting the water system, installing the pool liner, and constructing the pool, John needs to wait two days for the building materials settle and dry before filling the pool and turning on the fountain. How does John explain this delay in the schedule to the client? (For Ref Only, Question #: PM-02117) Group of answer choices It's mandatory It's discretionary It's a lag It's a lead